Variable pitch and reversing pro



Fb. 15, 1938. s. A. FARRELL VARIABLE PITCH AND REVERSING PROPELLER MECHANISM I 3 Sheets-Sheet l llllllgllii 4 "mum/,7

Original Filed March 1, 1955 & 1 G i N I Na N 1m 3 A an N NN I WITNESSES $64M 7% 2e fife 1222; 22:3178]! BY I I Feb. 15, 1938. s. A. FARRELL VARIABLE PITCH AN!)v REVERSING PROPELLER MECHANlSM Original Filed March 1',' 1935 3 Sheets-Sheet 2 *Z M V ATTORNEY$ I j WITNESSES Feb. 15, 1938. s. A. FARRELL 2,108,660

VARIABLE PITCH AND REVERSING PROPELLER MECHANISM Original Filed March 1, 1935 5 Shets-Sheet 3 III! III

Patented Feb. 15, 1938 UNITED STATES PATENT OFFICE- VARIABLE PITCH AND REVERSIING PELLER MECHANISM riso- Application March 1, 1935 Serial No. 8,952

- Renewed October 14, 1936 3 Claims.

This invention relates to a variable pitch and reversing propeller mechanism which may be used advantageously with marine and other craft.

An object of the invention is the provision of a. mechanism of the indicated character whereby variable direct and reverse thrust adjustment of the blades of a propeller may be accomplished from a remote point.

A further object of the invention is the provision of a mechanism of the indicated character whereby the pitch of the blades of a propeller may be varied at will to impart a direct or reverse thrust, and to make it impossible to vary the pitch of the blades beyond a maximum direct and reverse thrust value.

A further object of the invention is the provision of a propeller having angularly adjustable blades with efiiicient means operable to cause the simultaneous adjustment of the blades to vary the thrust thereof, and which means is automatically operable to prevent movement of the blades from their adjusted positions due to reactive pressure of the fluid medium in which the blades are op erating, to the end that power transmitting means may be employed, to operate the adjusting means as well as to drive the propeller, relieved at all times of any reactive strain from said blades.

Regarding the use of the invention in marine craft, it has the following advantages. It enables a man navigating a craft, to personally vary the propeller pitch, to get any possible thrust in either direction in two seconds, and to accomplish this without shock. The prime mover, Diesel, gasoline or steam turbine may be run at a. constant governed speed in the same direction at all times, and the emciency is that of a direct drive. The prime mover may be run at an economical speed while driving the craft at reduced speeds. It enables the use of a remote control. It enables the 0 provision of a driving mechanism which will always be in perfect mechanical and dynamic balance, simple, durable, light in weight, compact and comparatively inexpensive.

With the foregoing. other objects and advantages of the invention will appear from the embodiment thereof, which by Way of example, is described in the following specification and illustrated in the accompanying drawings, in which:

Fig. 1 is a longitudinal sectional and diagrammatic view of a mechanism embodying the features, portions thereof being broken away.

Fig, 2 is an enlarged transverse section taken on the line 22 of Fig. l.

Fig. 3 is an enlarged transverse section taken on the line 3-3 of Fig. 1.

Fig. 4 is an enlarged transverse section taken .on the line 4-4 of Fig. 1. I

Fig. 5 is an enlarged section taken on the line 55 of Fig. 1.

Fig. 6 is an enlarged section taken on the line 6i5 of Fig. 1.

Fig. 7 is a view of one of the details.

The mechanism of the present invention is hereinafter described by way of example, as applicable to marinecraft such as large steamships, naval vessels, and also smaller craft such as motor boats and launches.

The mechanism includes a propeller generally consisting of a hub Ill, blades H, there being three blades in the present instance, and a self locking gear set it carried by. the hub for each of said blades and operable to rotate the blade on its own axis to angularly adjust the same, for

the purpose of varying the pitch so as to obtain direct and reverse thrust, or in other words, I

varying the amount and direction of the propeller thrust. The hub It) has three bores or holes it; extending radially therein and spaced equi-distantly, and also has an axial bore as therein which communicates with the bores l3 and also opens through one end of the hub. Each of'the bores l3 provides a cross-sectionally round recess for one of the blades H and also for one .of the gear sets 52. Each gear set includes a circular case it whichfits within the bore, and is held in place against movement with respect to the hub by pins on the case which enter holes in the hub. v The case i5 is machined to receive an internal ring gear l? which is free to rotate in said case. The gear ll meshes with gears it, each or which is freely rotatable on anlarbor l9 screwed into or otherwise secured to the case it. The gear 57 also meshes with gears 26 each of which is freely rotatable on an arbor 2i screwed into or otherwise secured to the base or inner end 22 of the related blade ii. The gears iii are larger than the gears H8. The arbors l3 and 2% are disposed so that their gears 55 and 25 respectively will rotate freely on axes perpendicular to the axis of rotation of the hub, and parallel to the axis of rotation of the blade. A stub shaft 23 is disposed amally of the related blade H and one end thereof is loosely received in a socket 24 r in the base 22 and its other end projects through the case it into the bore i l. The shaft 23 has keyed fast thereto or formed integral therewith gears 25 and it respectively. The gear 25 is larger than the gear 26. The gear 25 meshes 2 i 2,1os,eeo

with the gears l6, and the gear 26 meshes with the gears 26. The inner end of the shaft 26 has secured thereto a bevel gear 21, the samebelng disposed in the bore I4. The base or inner end 5 22 of the blade II is cross-sectionally round in the form of a discand has a flange 29. Aspacing ring 29 fits within the blade bore i9 and also fits around the flange 26 and rests on the case IS. The blade bore I6 is threaded to receive a locking 10 ring 66 which is made of two parts in threading engagement with the internal threads 6| in the.

' higher than the flange 26, thereby permitting the blade II to rotate freely while being adjusted. In this manner the blade is positively locked in position without appreciable lost motion.

It will be apparent that each gear set i2 is of the epicyclic or planetary type. It will be obvious that when motion is transmitted to the shaft 26 of each gear set by rotating its gear 21 in one direction, the gear 25 will cause the gears l6 to rotate on their own axes, on their arbors 25 I9, and the gears i6 in turn wi il cause tpering 1 gear "and gear 26 td'rbtatfthe'gear will cause the gears 26 to rotate on their, arbors 2|, and to planetate around the shaftl26, due to the diflerencej in the size or proportion 'of the 30 gears l8 and 26 compared to the gears 26 and 26. In this manner each blade may be caused to rotate in one direction or the other, according to the direction in .which each of the bevel gears 21 is rotated, to angularly adjust the blade. the

desired degree to vary the amount and direction of the propeller thrust while acting in the water.

By reason of the locking characteristics inherent in each gearset |2 its blade is prevented from movement from its adjusted position in respouse to the reactive pressure of the water. In

this connection it is to be observed when reactive strain is imposed on eaclh blade, this will be transmitted to the arbors 2|'.=. This will tend to cause the gears 26 to impose a strain equally on the ring gear i1 and'the gear 26 and also the gear 25 which is integral therewith. The gears '|"and 26 are in mesh with the gears l8 and are tending to rotate in the same direction, consequently the gears I6 cannot rotate and the strain will be transferred through the, arbors l9 to the case l5 which is held fixed with relation to the hub. In this manner each blade will always and instantly be locked in its adjusted position against reactive movement from pressure of the 65 water while acting therein.

The flanged base 22-of each of the blades constitut'es a practical mounting for the blade to tion with the gear set I2.

60 There is provided means for driving or rotatingthe propeller, and said means is connected between the hubl6 of the propeller and the prime mover such as a Diesel, gasoline or steam turbine, or other power plant. The said means as comprises thecomponents or parts 35, 36, 31, 36,

69, 46, and 4| with suitable connections com pleting an assembly in perfect balance and sym- 1; shaft section 66. i ihe nut 42 bears on the flange I support it for angular adjustment in conjunc- 66, the latter being provided with a tapering opening to .flt around a taper portion of the shaft section 66 and the latter being keyed to the flange 66, as at. The component 61 con- .sists of a hollow shaft section having a flange 44 5 on one endwhich is secured to the flange 66 by bolts 46, and the other end has a dished flange 46. The component 66, consists ofa hollow shaft section of any preferred length, and has a dished flange '41 on one end-similar to the flange 46. i0

The component 69 consists of a ring which is disposed between the flanges- 46 and 41. Bolts 46 extend through the flanges 46 and 41 and the ring 69 to securely connect the shaft sections 6| and 66, and also to secure the ring 69. The i5 other end of the shaft section 66 has a flange 49. The component 46 consists of 'a shaft section having a flange 66 similar to the flange .46. The component 4| consists of a ring or annulus which serves as a spacer, the same being arranged be 20 30 Controllable means is provided for operating the gear sets l2 simultaneously to similarly adjust the blades L. The means consists of the following components or elements: A shaft section 66 extends through the shaft section 66 into 35 the bore l4 in the hub |6.. The bore of the hub I6 is tapped to receive a round nut 6| which has a bore 62therein to receive the outer end of the shaft section 66. In this manner the shaft section 66'is supported for rotation- Bevel gear 46 66 is fast on the shaft section 66' andmeshes with the bevel gear 21 of eachof the gear sets l2. The shaft section 66 has an oil hole 64 for the purpose-of introducing lubrication into the bore H to lubricate thev gearing. The stufling 5 box 66' is connected with the shaft section 35 and surrounds the shaft section 66 to prevent lubricationjfrom leaking past the shaft section 66 when the lubricant is injected under pressure through the hole 64. The shaft section 66 is flx- 5o edly secured asfat 66 to ,a carrier 61 loosely extending in the shaft section 68. The flanges 46 and 41- form a box or casing providing a chamber 66. The carrier 61 has a flange 69 which is disposed in the chamber 69, and theflange 69 is connectedwith a ring I6 also disposed within the chamber 68, the flange 69 be ing connected with the ring 16 in spaced reiation by. spacers shown in'dotted lines in Fig. 3,

and pins H are supported by the flange 69 and the ring 16, there being four pins in the present instance. Each pin 1| provides an arbor for a gear 12 which is freely, rotatable thereon between the flange 69 and the ring 16. Thus there are four gears 12 which rotate on axes parallel to the axis of the shaft section 66. The gears 12 mesh with teeth 19 on the ring 39. The

.ring 69 with its'teeth I6 constitute an internal gear. The gears 12 also mesh with an external gear 14 fastpn a shaft section 15. The gear;14 76 g e like the gear 12 is housed within the chamber 66. The shaft section 15 extends through-the shaft section 66 into a bore 16 in the shaft section 46. The carrier 61, ring", pins Ii, gears l2, l6, and I4 constitute a planetary speed changill "when engaged by the clutch element 99.

ing gear set, the function of which is to reduce the speed of the'shaft section 50 with respect to the shaft section I5, and to increase the torque between these shaft sections, and to increase the speed of the shaft section 60 with respect to the propeller drivingmeans 35-4I while rotating in the same direction of the latter.

Another gear set as follows is provided for causing the direct and reverse rotation of the shaft section '15 in response to the direct rotation of the drive shaft section 40, and through the intervention of said speed changing gear set causing the direct and reverse rotation of the shaft section 60. The flanges 49 and 50 and the annulus 4i as bolted together form a chamber 80. A duplex gear element consisting of a bevel gear 8| and a spur gear 82 is loosely mounted on the shaft section I5 within the chamber 80. A similar duplex gear element con-' sisting of a bevel gear 93'and spur gear 84 is keyed as at B5 to the shaft section 7.5 within the chamber 80. Stub shafts 88 are made fast in the annulus 4| and are disposed diametrically opposite each other to provide axes perpendicuwith the contact I05, the circuit will be closed causing current to flow through the coils I02 completing a magnetic circuit between the clutch element 95 and the element 99. ,This will cause the element 99 to move axially into contact with the element 95 thus holding the latter fast. Likewise when the blade I'I is moved into engagement with the contact I06 the circuit will be closed causing current to flow through the coils I04, thereby completing a magnetic circuit between the clutch element 99 and the clutch element 98. This will cause the clutch element 99 to move axially in contact with the clutch element 98 holding the latter fast. The contact I will be designated Astern, and the contact I06 will be designated Ahead.

In order to indicate the angular adjustment of the propeller blades ii there is provided the following means which is operated by the rotation of the control shaft section 60. The shaft section 80 has a right-hand threaded portion I I0 within the shaft section 31. A nut III is in threading engagement with the portion IIO. Pins II2 extend radially from the nut III diametrically lar to the axis of the snaftsection "l5l"ii'"beve'l opposite each other through longitudinal slots gear 81 is loosely mounted on each of the stub shafts 86 and meshes with the bevel gears 8| and 83. The spur gear 82 meshes with planetary gears 88 mounted on arbors 89 respectively supported by the annulus 4| and the flange 50. The annulus ll is recessed as at 90 to receive the gears 89. The spur gear 94 meshes with planetary gears 9|, similar to the gears 88, the gears 9| being mounted on arbors 92 respectively supported by the annulus 4| and flange 49, the gears 9| being disposed in recesses in the annulus similar to the recesses 90. The planetary gears 08 mesh with an internal gear 93 secured as at 94 to a ring clutchaelement 95 mounted for rotation on the annulus M. The gear 93 is disposed between the fiange 50 and the element 95. The planetary gears ,88 rnesh with an internal gear similar to the gear 93, the gear 95 being secured as at 97 to a ring clutch element 98, similar to the clutch element 95. The gear 98 is disposed between the flange 49 and the clutch element 98. The clutch elements 95 and 99 are made of magnetizabie metal. clutch element 99 surrounds the annulus 4| between the clutch elements 95 and 99. The clutch element 99 may be made in segments of magnetizable metal. The clutch element 99 is supported by stationary brackets 500 through the intervention of means i0I preventing rotation of the element 99 but permitting a limited amount of axial movement in opposite directions with respect to the clutch elements 95 and 98. The clutch elements 95 and 98 are free to rotate with the annulus ll at all times. except The clutch element 99 has a plurality of coils I02 directly adjacent the clutch element 95. The coils 402 are electrically connected in an electric circuit lllB. Coils 504 similar. to the coils I02 are embodied by the clutch element 99 directly adjacent the clutch element 98. The coils I04 are also electrically connected in the circuit I03. A switch S consisting of arcuate contacts I05 and 808 respectively and a blade I0! is provided. The contacts I05 and H36 and the blade HII are included in the circuit 603. The circuit I03 also includes a suitable source I08 of electrical energy. The switch S will be arranged at a remote point under the control. of a navigator. When the blade I01 is moved into engagement A ring;

H3 respectively in the shaft section 31. The pins H2 in the, slots H3 prevent rotation of the nut III with respect to the shaft section 31, but per-v mit axial movement with respect thereto. The pins II2 tightly fit in holes in a circular flange II4 on a disk II5 slidable axi lly on the shaft section 31. The disk H5 and its flange H4 are in two half-sections secured to each other. An arm H8 is mounted for rocking movement on a shaft Ill. The arm H6 is bifurcated, and the furcations thereof are disposed on opposite sides of the disk H5 normally out of contact therewith but in close proximity to the disk. A sprocket H8 is fast on the shaft IIl. A chain |I9 encircles the sprocket H8 and a sprocket I20 fast on a shaft 92L A pointer I22 is mounted on the shaft l2! for movement therewith. The pointer I22 moves with respect to a suitable'graduated scale l23 to indicate any change in the pitch or the adjustment of the propeller blades H. The scale H3 and its pointer I22 may be arranged near the switch S so that'indications regarding the pitch or adjustment of the blades II will be transmitted to the navigator.

In order to automatically disengage the clutch element 99 from either the element 95 or 98, when the propeller blades lI have reached the angle necessary for full speed, either astern as when the element 95 is held, or ahead, as when the element 98 is held, there is provided the following means. Contacts I25 and I26 respectively are arranged in relation to the pointer l22. Pointer in will be made of conducting material. The pointer H2 and thecontacts 25 and I26 are electrically connected in the circuit I03. When the propeller blades II are in their neutral positions, the pointer |22 will be disposed vertically and equally in engagement with the contacts I25 and I26. Therefore when the switch blade i0! is moved into engagement with either the contact M5 or the contact I05, the circuit I03 will be closed to accordingly adjust the blades II for reverse thrust astern, or a direct thrust ahead. While the adjustment of the blades is taking place, the shaft 99. The means are so devised that this action' will take place when the blades II have reached their maximum thrust value eitherfor imparting motion ahead or astern. When the propeller blades II have been adjusted to their maximum value for-direct or reverse thrust, the circuit I83 8 may be closed by moving the switch blade I81 into engagement with the contact I85while the pointer I22 is fully in engagement with the contact I28 to cause adjustment of the propeller blades II to impart a reverse thrust astern, whereas the switch blade I81 maybe moved into engagement with the contact I88 while the pointer I22 is fully engaged with the contact I28 to cause the adjustment of the blades II to impart a direct thrust ahead.

The operation of the mechanism is as follows: Assume the propeller blades II to be in their neutral positions (zero pitch), and the pointer I22 at zero as shown in Fig. l, with the shaft section 48 being driven in a clockwise direction lookingat the same from the right-hand end. Let us further suppose that the ship is at a pier or dock, and it is desiredto get out into the stream by backing. The navigator will move the switch. blade I81'into engagement with the contact I85 while watching the pointer I22. Thiswill close the circuit I83 throughthe coils.l82 causing the while the carrier 81 clutch element 99 to engage the element 95 and i hold the latter against rotation. The gear .93 being secured to the clutch element 95 will also be held against rotation. This will cause the gears 88 'to rotate counter-clockwise. on their own axes, while-planetating clockwise, causing the gears 82 and 8| to rotate clockwise. This will cause the gears 83 and 88 to rotate counterclockwise through'the, intervention of the gears 81. "Thegears 83 and 88 rotating counter-clock- .wise will cause the shaft section 15 to rotate in the same direction. The planetary gears 9| will be rotating idly on their own axes clockwise and will be planetating clockwise causing the internal gear 98 and the clutch element "98 to whichit is secured to rotate idly in a clockwise direction. The rotation of the shaft section 15in in the same direction. The gear. 18 causes the gears 12 to rotate clockwise on' their own axes and also to planetate in a counter-clockwise direction, is also caused to rotate in a. counter-clockwise direction by the pins 1 I at a reduced speed compared to that of the shaft section 15, but slightly faster than the means 35-. The carrier 61 being secured fast to the shaft section 88 causes it to rotate at the reduced speed in a counter-clockwise direction. The

shaft section 88 causes rotation of the gear 83 therewith, which in turn causes the simultaneous rotation of the gears 21 of the gear sets I2? This will cause the rotation of the shafts 23 and gears f 25 and 28 connected therewith in a clockwise direction as viewedin Fig, 6. The gears 25 and 28 will cause rotation of the gears I8 and 28 respectively in a counter-clockwise direction. The

"gears I8 cause the internal gear I1 to rotate in- 1a counter-clockwise direction. Due to the erience in the proportion of the gears 25 and I8 compared to the gears 28 and 28,. the gears 28 will -Jtake purchase on the internal gear I1 and planetate'in a counter-clockwise direction causingthev a counterclockwise direction causes the gear 18 to rotate clutch elements 95 and 98 to blades II to move in the same direction to an angular position causing a reverse thrust astern.

Whilethis action is taking place, the nut III" will be caused to move axially toward the hub N by the shaft section 68, due to the fact that parts I I8 to 12! inclusive, toindicate on the scale I23, the degree of astern adjustment of the blades II. By moving the switch blade -I81into en gagement with the' contact I85, the circuit I83 will be closed through the coils I88 thereby causelement 98 and hold the latter against rotation.

.The gear 98 being secured to the element 98 will be held fast. This will cause the gears 9| to'rotate counter-clockwise on their own axes while planetating in a clockwise direction, thereby causing the gears 83. and to rotate in a clockwise "direction and as a consequence the shaft section a 15 will be caused to rotate in a clockwise direction; i

25 the shaft section 88 and its gear 83 to rotate ina The gears of the speed reducing gearing will cause clockwise direction at reduced speed compared to the speed of the shaft section 15.. This will] cause the operation of the gear sets I2 in a manneropposite to. that hereinbefore described,

blades" for a direct thrust ahead: The shaft section 88 rotating clockwise like the shaft section 81 but at a faster rate of speed, causes the nut III to move axially'toward the carrier 81. Through the intervention of the parts I I2-I2l,

.30 thereby causing adjustment of the" propeller the pointer l22iwill be movedt'o indicate on the scale I23, the ahead adjustment of the blades II.

Whenthe clutch element 99 is disengaged and the drivingmeans is rotating all of the gearing is rotating about the axis .of the driving means in j a nascent state. The propeller will be driven at the same speed as the shaft section 88 and in.

the sam the sam direction which is clockwise, andat same direction when the clutch element 99 is dis- ;engagedr If desired an emergency brake means I38 may automatically release theclutch when the propeller blades have reached the pitch limit,-either backing or going ahead at full speed. In other words, it the switch blade I81 isput on theiastern time. the shaft sections 88 and 15" will ,berotating at the same speed-and-in the contact I85 and left there, the propeller blades will be turned on thelrown 1 axes in such manher that the ship willback full speed astern, and the clutch will be automatically released at the instant the propeller blades have been ad justed :for extreme thrust. The same is true ifthe switch blade I81 is put on the ahead contact I88. Furthermore, after the extreme pitch has been given the propeller blades in either direc- 'tion, no mistake can be made regarding further changes in the pitch of the blades desired. If

the navigator wishes to vary-the pitch of theblades to attain changes in speed, the switch 8 must be closed ahead or astern, and when the indicator shows the pitch for the desired speed; 1

the switch must be opened thereby-releasing the clutch and so leaving the blades at the desired.

pitch. r

18 ing the clutch element 99 to contact. theclutch It is to be understood that the invention is not restricted to the precise arrangementof parts shown and described, as details of construction may be modified and rearranged without depart-= ing from the spirit of the invention, the scope of which is limited only by the terms of the appended claims.

I claim: I I

1. In a variable pitch and reversible propeller mechanism, in combination, a rotatable shaft, an intermediate rotatable shaft in axial alinement with the first shaft, a hollow propeller driving shaft through which the first and intermediate shafts extend, speed changing means connected with all of said shafts to change the speed of the first shaft with respect to the driving shaft, and means connected with the intermediate shaft and driving shaft to operate the speed changing means, to cause the first shaft to rotate in the same direction as the driving shaft but faster, or in a reverse direction thereto, in response to the direct rotation of the driving shaft.

2. In a variable pitch and reversible propeller mechanism, in combination, a rotatable shaft,

an intermediate rotatable shaft in axial alinement with the first shaft, a hollow propeller driving shaft through which the first and intermediate shafts extend, speed change means to change the speed of the first shaft with respect to the driving shaft, said means comprising a carrier fast on the first shaft, freely rotatable planetary gears on said carrier, an external gear fast on said intermediate shaft, and an internal gear fast on said driving shaft, said planetary gears meshing with said external and internal gears; and means connected with the intermediate shaft and driving shaft to operate the speed changing means, to cause thefirstshaft to romediate shafts extend, speed changing means connected with all of said shafts to change the speed of the first shaft with respect to the driving shaft, and means connected with the intermediate shaft and driving shaft to operate the speed changing means, to cause the first shaft to rotate in the same direction as the driving shaft but faster, or in a reverse direction thereto, in response to the direct rotation of the driving shaft, said last means comprising a duplex gear loose on said intermediate shaft, a duplex gear fast on said intermediate shaft, freely rotatable planetary gears carried by the driving shaft for each of said duplex gears and meshing with one series of teeth thereof, other freely rotatable planetary gears carried by said driving shaft between said duplex gears and meshing with their remaining series of teeth, an internal gear for each duplex gear meshing with said first planetary gears, and a device to hold and release said internal gears.

STEPHEN A. FARRELL. 

